Producción acuapónica de tilapia y lechuga en regiones semiáridas: eficiencia hídrica y reciclaje de nutrientes

Background: Water scarcity and food insecurity in arid regions such as the Comarca Lagunera demand sustainable production models. Aquaponics, integrating fish and plants in a closed-loop system, emerges as a viable alternative to optimize resources and strengthen food self-sufficiency in rural areas. Objective: To evaluate the productive performance, water efficiency, and technical and economic feasibility of a low-cost aquaponic system combining tilapia (Oreochromis niloticus) and lettuce (Lactuca sativa) under semi-arid conditions. Methods: Three production systems were compared under semi-controlled conditions for 18 weeks: aquaponics (fish and plants), aquaculture (fish only), and hydroponics (plants only). Growth performance, water consumption, nutrient recycling, and operating costs were analyzed. Results: The aquaponic system increased final tilapia weight by 22.3%, lettuce root development by 28%, and reduced water use by 30% compared to hydroponics, while achieving 89.3% nitrate absorption and 38.5% lower operating costs. Implications: The results demonstrate that aquaponics can improve water-use efficiency, reduce the use of fertilizers and plastics, and promote circular economy models applicable in rural communities with limited resources. Conclusions: Aquaponics is a technically and economically feasible alternative for semi-arid regions, integrating water efficiency, nutrient recycling, and sustainable food production, contributing to food security and local resilience.